The project
Changes to the Water Services Act 2021 have meant that when you supply more than one household by the same water source, you are classified as a drinking water supplier and therefore responsible for ensuring the provision of safe drinking water. Some examples of people who may now be considered a water supplier include: farmers, subdivisions (with a communal water supply), holiday apartments, schools, community halls, ski fields, maraes and campsites.
Rules and regulations under the Act reflect the size of the population served, with fewer rules for smaller supplies. As a supplier, you can choose to either meet requirements for the relevant size supply under the Drinking Water Quality Assurance Rules (DWQAR) (2022 updated 1 January 2025) or follow an ‘Acceptable Solution’ prescribed by Taumata Arowai.
We have been involved in helping our clients assess their water supplies and provide advice on the best path for them to ensure that they meet their obligations as a water supplier.
What we did
The studies have comprised the following tasks:
Water Supply Reviews
We undertook a review of existing water supplies, the number of people/households supplied, and the current treatment systems.
From here we provided advice on whether the owners are better to proceed with an ‘Acceptable Solution’ or aim to meet the requirements of the DWQAR.
Treatment Solutions
We worked with our clients and industry to determine the best treatment solutions for their water supplies while also meeting the ‘Acceptable Solution’ or DWQAR pathway chosen.
Water Safety Plans
When the DWQAR pathway is chosen, a Water Safety Plan is required. The purpose of the Water Safety Plan is to protect people from serious risk, providing a mechanism to ensure complete understanding of the water supply proportionate to the scale and complexity of the supplies.
Key items, included in the Water Safety Plan are:
- Identification of hazards and risks, including details on how to manage, control and eliminate these risks.
- Multibarrier-approach treatment processes.
- Monitoring requirements.
- Details on how to comply with source, treatment and distribution rules within the DWQAR.
- Response to events and emergencies.
Water Quality Sampling and Interpretations
We assisted with water quality sampling and interpretation of results. We compared water quality sampling results alongside Water Services Regulations 2022 (Drinking Water Standards for NZ), which sets Maximum Acceptable Vaues relating to microbiological, inorganic, organic and radiological determinands, and the Aesthetic Values for Drinking Water notice 2022, which sets taste and staining thresholds and thresholds so that water treatment is effective.
Where issues were identified, advice was provided to upgrade water supplies to ensure that the water supply provided is safe.
Key findings and solutions
Every water supply is different, and whether an ‘Acceptable Solution’ or following the DWQAR is the best path to follow depends on the individual water supply.
The advantages of an ‘Acceptable Solution’ is that it is a prescribed solution, and a Water Safety Plan is not required. Typically, the ‘Acceptable Solution’ is a good pathway for a very small or small water supply.
The advantages of following the DWQAR is that that there may be cost benefit gains (particularly for a medium water supply). However, a Water Safety Plan is required.
Treatment solutions for roof water, surface water and groundwater can have different requirements. It is important to tailor the treatment solution to each water supply for it to work effectively.
Water quality sampling is key to ensuring that safe water is being supplied.
